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%I #5 Dec 18 2015 18:18:43
%S 0,0,28,5734,5524854,28716109350,810027275568580,124090541934393885346
%N Number of n X n 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero
%C Diagonal of A230275
%e Some solutions for n=3
%e ..0..0..1....0..1..2....0..1..0....0..2..2....0..2..1....0..2..1....0..2..1
%e ..1..0..2....2..1..0....2..2..2....1..1..0....1..2..0....1..2..0....1..2..0
%e ..2..0..1....2..0..2....1..0..2....2..0..2....0..1..0....0..2..1....0..1..2
%K nonn
%O 1,3
%A _R. H. Hardin_, Oct 14 2013